Building or paving block



` (No ModeL). 2 Sheets-Sheet 2.

@.MGRAHAl. BUILDING QB. PAVING K.

No 707?. Patenteam 8,1892.

INVENTOR:

Geyef ra am,

" To all whom it may concern.'

I5 parts in the diterentviews.

UNITED STATES PATENT FFiCE@ GEORGE'M. GRAHAM, OF CHICAGO, ILLIOIS.

SPECIFICATION forming part of Letters Patent No.

470,377, dat-ec Marcil e, 1892.

f Application led- May 1l, 1891.v Serial Noi 3921.391. (No model.) v

Be it known that I, GEORGE M. GRAHAM, citizen of 'theUnited States,residing at 'Chi-1 cago, in the county of Cook and State'oflllinois haveinvented certain new and useful Im- 5 n n l l proveniente 1n BuildingorPavingBlocks and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will nable othersskilled in the artfto which it appertains to make and use the same.

My present invention relates to that type of building or paving'blocksthe abutting sides. or surfaces of which are provided withcoulnterpartprojections and recesses, so as to interlock together and beheld inproper position or alignment', and particularly such as form thesubject-matter of Letters Patent No. 401,492, 'issued to me April16,1889, the object of the present improvement being to provideV animproved construction of such blocks, in which the surface format-ion issuch as to afford a perfect interlocking of the one block with the othercontiguous block or blocks and which at the same time avoids'a sharpangular form inthe cavities or recesses in said interlocking surfaces,that has heretofore been a serious element of weaknessin formerconstructions', owing to the fact that such sharp angularity of therecesses serve as a ready starting-point for a fracture or crack in themain body of the block whenexposed to undue' or unequal strain,sudden orexcessive impact, dsc. I attainV such object by the construction ofparts illustrated in the accompanying drawings, in which``4 Figure 1 isa facev view vor elevation .of the preterredformpt rnyimproved buildingor paving 'bl'cckasbes Y. dapted for general use in large constructions;Fig. 2, a section of the same at line 1113 an elevation of a simplerform 'of theblock; ,Fi-g. i, a section of an elementary meinber'- 'ofthe present improved construction. 'y

"Similar numeralsof reference indicate .like

-As-representcdin the drawings, my improvedbuildinggorgpaving vblockwill have-a plane outer face 1, suitably divided or otherwise ornamented.with ydepressions and proa, 5o jections, and an inner face or back 2elther' plane, ornamental, or formed with interlocking ridges anddepressions for interlocking jter'nating ridges 47 and follan equal"radii,

'which in both` and braced Vin y`pris'uint-ic" formations inr "Strengthbeing the outcome, owing to um j' The four the block are ofaniinterlocking with a similarly-forista bloei; infine/construe!tionof'tvallsV havinga' much greater thickness than that of ,asingle"building-block vof the SsK which in thepresentiuvention'consistsof "al-l 1 depressions `8, curved ber of rows"'or; series cesses of'asegmental or staggered Figs. l and 2.

' In its elementary form, as shown in Fig. 4, the block will be of anapproximately spherical shape, blending into that of van `irregularhexagonal form, the to bottom, and sides being formed on reversed curvesof equal radii, .asheretofore described, and the end or ends formed'plane, as shown,.to constitute an abutment fora similarly-formedelementary block. This elementary I or individualform of the v which inAmy mostperfect and preferred construction divides the sideslor ofproject-ions andrep 'spherical contour, the one row orseriesbeingintermediately placed with relation to the' Inext adyjacent row or rows,as clearly illustrated in block is not intended forA practical use, asit does notafford the universal interlocking features-that its integralcombinations Will'afford, as illustrated in Figs. 1, 2, and 3.

In the formation ,ofy my improved building or paving blockany requirednumber of the elementary tegrally united together to constitute a of thesize and small enough to forms above described may be inblock dimensionsrequired, either be readily placed by hand or large enough to require aderrick in handling.

. The practical advantages or merits arising from the present improvedconstruction are similar 4to that set forth in my aforesaid Let-- tersPatent in relation to the construction therein shown superior.difference in the present construction being that the joints between theblocks, constructions are supported form ofthe adjoiuingblock, are intions and` recessesinstead of the angular` or avoidance of any tendencyto-fracture or v4and described, the only and.

every direction by the,so"lid v l the pres- 4 ent improvementformed bycurved projec-" roo the former, an added .A y

4 byLett'ersfPatent, isw;

cracking, as no starting-point is afforded for a crack or fracture,while, on the other hand, the former angular or prismatic constructionaorded at each angular depression a ready starting-point for a crack orfracture of the block under irregular strain, accidental impact, 85o. Inthe manufacture of my improved builds ing or paving block any suitablematerial may xo be exnployed-either artificial stone, terracotta,clay,met al, or other suitable compound or composition-in accordance.with thefspecial uses to which the blocks maybe applied. Having thusfully described my 'said inven- 15 tionmhatl claim as new, and desire tosecure 1.A building or paving block. having'i'is sides 3, 4, 5, 'and 6formed with interlocking projections 7 and recesses 8,-of a segmentalspherical form and equal radii, substantially as set forth. ,v

2. `Aflouilding or paving block navngits sides 8,4,-5; and 6 formed withrows or series of interlocking projections 7 and recesses S,

intermediately arranged or staggered and of 25 a. segmental sphericalform and equal radii, l

substantially as setl forth. ,Y In testimony whereof I afx mysignature1n presence of two'vvtnesses.

.y Witnesses: fr

' 'ROBERT BURNs, BYRNE.

